Yeah, doesn't frostbolt have a casting tine of 2? And arc blast is 2.5? But something that's really interesting is that classes like frost benefit the most from weapons like Nibelung because Nibelung procs off harmful effects rather than damage so say I cast a frosbolt. It does damage, slow, winters chill and if frosbite procs(regardless If the target is immune or not) that's 4 harmful effects in one shot which gives a much greater chance of getting an actual proc. Overall frost is better and brings some raid buffs but is still too lacking for us to take.